65 lines
1.5 KiB
ReStructuredText
65 lines
1.5 KiB
ReStructuredText
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.. Permission is granted to copy, distribute and/or modify this
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.. document under the terms of the GNU Free Documentation License,
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.. Version 1.1 or any later version published by the Free Software
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.. Foundation, with no Invariant Sections, no Front-Cover Texts
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.. and no Back-Cover Texts. A copy of the license is included at
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.. Documentation/media/uapi/fdl-appendix.rst.
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..
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.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections
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.. _common:
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###################
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Common API Elements
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###################
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Programming a V4L2 device consists of these steps:
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- Opening the device
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- Changing device properties, selecting a video and audio input, video
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standard, picture brightness a. o.
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- Negotiating a data format
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- Negotiating an input/output method
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- The actual input/output loop
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- Closing the device
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In practice most steps are optional and can be executed out of order. It
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depends on the V4L2 device type, you can read about the details in
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:ref:`devices`. In this chapter we will discuss the basic concepts
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applicable to all devices.
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.. toctree::
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:maxdepth: 1
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open
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querycap
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app-pri
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video
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audio
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tuner
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standard
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dv-timings
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control
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extended-controls
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ext-ctrls-camera
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ext-ctrls-flash
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ext-ctrls-image-source
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ext-ctrls-image-process
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ext-ctrls-codec
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ext-ctrls-jpeg
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ext-ctrls-dv
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ext-ctrls-rf-tuner
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ext-ctrls-fm-tx
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ext-ctrls-fm-rx
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ext-ctrls-detect
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format
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planar-apis
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selection-api
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crop
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streaming-par
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